U.S. Pat. No. 3,540,989 to Webb discloses a process for reducing secondary electron emission wherein an electrode is exposed to an inert, ionizable gas and thereafter, a carbon containing gas is introduced. The second gas ionizes and a carbon film forms on the electrode.
Gutnajer U.S. Pat. No. 3,619,286 discloses a process wherein a graphite electrode is coated with pyrolytic graphite. Prior to coating, a graphite mold is exposed to an argon atmosphere at high temperature to induce carbonization of the binder.